Persist renderer state on server via SQLite and WS APIs

- Add shared renderer state contracts and websocket methods
- Implement server-side SQLite-backed renderer state store with Node/Bun adapters
- Migrate web store hydration/persistence from localStorage to server state, with legacy fallback
- Add contract, store, and websocket persistence tests
4d976b8bf7Julius Marminge committed on 2/18/2026, 5:15:51 AMparent0c50a2d
13 files changedLine totals unavailable